I have a problem which i have no clue on

I drive , turbo boosts fine til 0.5 then flutters up and down between the .5 and 1 bar making like a swooshing sound after bout 5 - 10 seconds goes normal and boosts fine

I have changed my boost solenoid , maf , coilpacks , dumpvalve and hoses to samco's

Running a td05 16g , Blitz dumpvalve

I also have a apexi ecu so can't read fault codes its a 93 wrx/sti

Please Help

 

mine did this when i put a free flow filter in and centre de cat, because more air is being charged and going through faster the boots solinoid cant keep up as you now are boosting over its target booost setting so it fluctuates for a second or two and setles down but as soon as throtle is presses it starts again. i got round this by means of a dawes device set to sensible boost level till i had my re map done it run sound just dont go over board with boost, i set mine on a uk 2000 myoo to 15 psi and ran that for 12 month wi no hastle

 

You have a PFC so at what point did this start to happen? Have you done any mods to the car since that last remap??

 

just changed my hoses , plugs , coilpacks and other than that remove my bung occasionally
my boost is set at 1 bar and have adjusted 2 lower boost to see if it still happens and it does just not as bad ?????????????

 

you could plug a standard ecu in to do a fault code heck to rule out any of the sensors?

 

plugging in standard ecu will not work i have been told will not read fault as it is on apexi but i don't know maybe some 1 will clarify this

 

if the fault is a car sensor plugging the original ecu and running a fault test will tell you where/if the fault is on one of the sensors, as i am not sure weather the apexi does fault checks?

 

might try it out